Field of the Invention
The present invention relates to a cooling device, alight source unit including this cooling device, and a projector including this light source unit.
Description of the Related Art
In these days, data projectors are widely used on many occasions as an image projector for projecting a screen or a video screen of a personal computer and images based on image data recorded on a memory card or the like. In these data projectors, light emitted from a light source is collected on a micromirror display device called a Digital Micromirror Device (DMD) or a liquid crystal panel, so that a color image is displayed on a screen.
The projectors include a light source unit, and the light source unit is heated when it generates light for emission. Thus, an interior of the light unit is cooled by a cooling device.
For example, a light source unit described in Japanese Unexamined Patent Application Publication No. 2015-222301 includes a first heat sink for a first light source which is disposed on aside of the first light source, a second heat sink for a second light source which is disposed on a side of the second light source, and a first cooling fan which is made up of an axial-flow type blower and which is disposed between the first heat sink and the second heat sink so as to be parallel thereto.
It is known that an air flow speed and an air flow amount of such an axial-flow fan are quickly and drastically reduced in such a state that the axial-flow fan is disposed so that an intake side thereof is situated near, for example, a wall surface or the like. Due to this, in a so-called draw cooling method in which a heat sink is disposed on an intake port side of a cooling fan, when attempting to drive the cooling fan efficiently, a certain distance needs to be ensured between an intake port of the cooling fan and the heat sink.
In a case where the certain distance is ensured between the cooling fan and the heat sink, however, a dead space is increased, and a limitation is imposed on the layout of the cooling fan and the heat sink. This causes a problem in that it is difficult to reduce the size of a main body of the projector while ensuring the required cooling performance of the projector.